eigenmann: the FRESHWATER FISHES OF BRITISH GUIANA 427 



Snout very slightly pointed in young specimens, blunt in adults; mouth rather 

 large; gape straight, reaching about two-thirds of the distance to the eye; upper 

 jaw included; lower jaw projecting; a single row of teeth in each jaw; eyes rather 

 small; caudal peduncle one-half the length of the snout or less; pectorals 2.25-3 

 in the head; origin of the anal behind the pectorals on the vertical from a point 

 about 1.5 times the snout behind the head. 



Ground-color varying from a light slate-gray in young specimens to a light 

 orange in adults; a series of transverse white stripes crossing the body in young 

 individuals, which stripes widen and become yellow with age, so that the adults 

 are yellow, banded with black; dorsal parts washed with a dark chocolate-brown 

 containing numerous black spots; fins translucent, mottled with black or brown. 



Subfamily Sternopygin^e. 



Sternopygus Muller and Troschel. 



Gymnotus Cuvier, Regne Animal, II, 1817, 235. — Gill, Proc. Acad. Nat. Sci. 



Phila., 1864, 152. 

 Sternopygus Muller and Troschel, Horae Ichth., Ill, 1849, 13. 

 Type, Gymnotus macrurus Bloch and Schneider. 



Distinguished from all other Gymnotids by the free orbital margin; no caudal 

 fin; teeth in patches on both jaws; snout short and stout. 



272. Sternopygus macrurus (Bloch and Schneider). 

 Gymnotus macrurus Cuvier, Regne Animal, TI, 1817, 237. 

 Carapus arenatus Eydoux and Souleyet, Voy. Bonite, Zool., I, 1836, 210, pi. 8, 



fig. 2. 

 Sternopygus macrurus Muller and Troschel, Horse Ichth., Ill, 1849, 13. — 



Steindachner, "Die Gymnotidse," 1868, 11 (Surinam). — Eigenmann, Repts. 



Princeton Univ. Exp. Patagonia, III, 1910, 450. 

 Sternopygus marcgravii Reinhardt, Vidensk. Med. Nat. For. Kjobenhavn, 1852, 



Carapus sanguinolentus Castelnau, Anim. Am. Sud, Poiss., 1855, 85, pi. 32, fig. 1. 

 Sternopygus carapus Gunther, Catalogue, VIII, 1870, 7. — Steindachner, 



"Flussfische Siidamerika's," ii, 1881, 44 (Surinam). 

 Gijmnotus carapus (not of Linnseus) Eigenmann and Ward, Proc. Wash. Acad. Sci., 



VII, 1905, 175. 



One hundred and four specimens, 155-500 mm. Botanic Garden. (C. M. Cat. 

 No. 1764a-t; I. U. Cat. No. 12591.) 



